Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Related Party Transaction [Line Items]
Accounts receivable from related party	$ 4,455	$ 5,033
Accrued liabilities to related parties	2,045	4,594
Goodwin Procter LLP [Member]
Related Party Transaction [Line Items]
Accrued liabilities to related parties		300
Goodwin Procter LLP [Member] \| Intellectual Property [Member]
Related Party Transaction [Line Items]
Payments for legal matters	400
Goodwin Procter LLP [Member] \| Intellectual Property [Member] \| Maximum [Member]
Related Party Transaction [Line Items]
Payments for legal matters		100
Astellas [Member] \| Collaborative Arrangement [Member]
Related Party Transaction [Line Items]
Revenue related to collaboration agreements	21,600	18,000	$ 25,700
Expense related to collaboration agreements	9,800	11,400	$ 4,000
Accounts receivable from related party	4,500	5,000
Accrued liabilities to related parties	$ 2,000	$ 4,300

Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The amount of cash paid for the settlement of litigation or for other legal issues during the period.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

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